Disposed Bauxite Residue
Production of alumina from the Bayer’s process results in the generation of a tremendous amount of toxic waste called ‘Red Mud.’ Production of 1 to 3 tons of alumina requires 3.3 to 6 tons of bauxite ore, which results in the production of 1.5 to 4 tons of red mud. The high soda content in red mud makes it toxic for plants and animal life if not disposed of properly. The annual production of red mud reaching 120 million tons and increasing stockpiles worldwide raises the concern regarding handling, storage, and recycling. The current application is limited to raw material in making building materials. Red mud is rich in elements like aluminum, iron, titanium, and rare earths. The presence of high content of hematite in red mud makes it an attractive iron source; however, the alkali nature makes it an undesirable feedstock for the blast furnace.